1. Field of the Invention
The invention relates to an internal combustion engine spark ignition system. More specifically, the invention relates to a pencil ignition coil designed to be mounted to a spark plug without damaging the pencil ignition coil or the spark plug.
2. Description of the Related Art
The internal combustion engine can be categorized in several ways. One such way to categorize the internal combustion engine is whether the design requires a spark to combust the fuel within cylinders of the internal combustion engine. Diesel engines do not require a spark to be generated within the cylinders thereof. Non-diesel consuming internal combustion engines do, however, require a spark to ignite the fuel within the cylinders thereof.
With regard to non-diesel internal combustion engines the design thereof include the utilization of pencil ignition coils to operate the spark plugs. Recent developments in internal combustion engines include coils, sometimes called pencil coils, that are designed to be mounted directly to the spark plug. In addition, the pencil ignition coil is designed to primarily extend through the spark plug bore of the internal combustion engine. In other words, the pencil ignition coil is a long, thin pencil ignition coil designed to utilize the wasted space of the spark plug bore of the internal combustion engine.
Inherent in the design of a pencil ignition coil is the requirement that the pencil ignition coil be positively mounted to the engine and electrically connected with the terminal of the spark plug. Once the spark plug has been screwed into the spark plug bore, one way to positively mount to the engine and electrically connect the pencil ignition coil to the spark plug is to friction fit the pencil ignition coil over the terminal of the spark plug. To ensure the pencil ignition coil does not disengage the spark plug during the operation of the internal combustion engine, the friction fit (or press fit) must be strong enough to withstand operational forces that might jar the pencil ignition coil from the spark plug. Creating the friction fit is problematic because the impact force used to create the friction fit by forcing the pencil ignition coil over the spark plug may cause damage to the pencil ignition coil or the spark plug. If such damage occurs, either the spark plug and/or the pencil ignition coil will have to be replaced prematurely.